The aim of this research project is to develop and optimize methods for noninvasive coronary artery imaging using magnetic resonance (MR). Because coronary artery disease remains the major cause of death in the western world, a reliable noninvasive imaging method would be of enormous benefit. This continuation application is based on our work conducted over the past four years as part of an NHLBI program (RFA NIH-86-HL-31-H). Specifically, the research plan in this application concerns the development of the following methods: 1) a projective imaging method involving the selective tagging of blood flowing into the coronary arteries; 2) a sequential two-dimensional slice imaging method relying on in-flow enhancement of blood; and 3) a blood imaging method using NMR parameters for blood enhancement. With these three methods, we have begun producing MR coronary angiograms on humans on a consistent basis. An important aspect to the methodology is the use of high-speed imaging techniques, which enable breath-held scanning to minimize problems with respiration. Following optimization, these methods will be evaluated on subjects with known coronary artery disease to determine clinical efficacy, using comparative studies with x-ray contrast angiography.